L\'{e}vy flights in random environments

Abstract

We consider L\'{e}vy flights characterized by the step index $f$ in a quenched random force field. By means of a dynamic renormalization group analysis we find that the dynamic exponent $z$ for $f<2$ locks onto $f$, independent of dimension and {\em independent} of the presence of weak quenched disorder. The critical dimension, however, depends on the step index $f$ for $f<2$ and is given by $d_c=2f-2$. For $d<d_c$ the disorder is {\em relevant}, corresponding to a non trivial fixed point for the force correlation function.